1. Field of the Invention
The invention generally relates to receivers for receiving scanning signals and, in particular, to a microwave landing system (MLS) receiver for receiving scanning signals provided by an MLS ground system.
2. Description of the Prior Art
The International Civil Aviation Organization (ICAO) has adopted a time reference scanning beam (TRSB) technique as the standard for microwave landing systems. MLS ground systems provide elevation (EL) and azimuth (AZ) scanning beams, each including a TO scan followed by a FRO scan, defining the area of coverage of the ground system. An MLS receiver located in an aircraft receives the EL scan and AZ scan and is able to determine the azimuth and elevation locations of the aircraft with respect to the ground system. As part of its function, an MLS receiver monitors certain performance parameters as compared to the dynamic limits of the aircraft. Specifically, an MLS receiver indicates a flag when the rate of change of the azimuth or elevation angles surpasses a predetermined dynamic limit for the aircraft.